RESUMEN

The large-scale production of chicken eggs results in a substantial amount of eggshell (ES) residue, often considered as waste. These discarded shells naturally decompose in soil approximately within a year. Eggshells (ES), comparatively contribute lesser towards environmental pollution, contain a remarkable amount of calcium, which can be converted into various valuable products that finds applications in industries, pharmaceuticals, and medicine. Among the diverse applications of ES, most effective and promising applications are removal of heavy metals (Cd, Cr, Pb, Zn, and Cu) ∼93-99 % metal adsorption capacity and capturing of flue gases (CO2 and SO2) from the environment. With ES having a maximum CO2 sorption capacity of 92 % as compared to other sources, and SO2 adsorption capacity of Calcined ES∼11.68 mg/g. The abundance, low cost and easy availability of CaO from ES makes them sustainable and eco-friendly. Additionally, its versatility extends beyond environmental prospects, as it is widely used in various industries as a catalyst, sorbent, fertilizer, and calcium supplement in food for individuals, plants and animals, among other diverse fields of study. Owing to its versatile applications, current review focuses on structure, chemical composition, treatment methods, and valorization pathways for diverse applications, aiming to reduce the eggshells waste and mitigate environmental pollution.

Asunto(s)

Cáscara de Huevo , Cáscara de Huevo/química , Animales , Pollos , Metales Pesados/análisis , Administración de Residuos/métodos , Contaminación Ambiental/prevención & control , Adsorción

RESUMEN

Water recycling and reuse are cornerstones of water management, which can be compromised by the presence of pollutants. Among these, pharmaceuticals can overcome standard water treatments and require sophisticated approaches to remove them. Sorption is an economically viable alternative limited by the need for sorbents with a sorption coefficient (Kd) higher than 500 L/kg. The cross-linking of dextrin (Dx) with divinyl sulfone (DVS) in the presence of 1 mmol or 5 mmol of ibuprofen (IBU) yields the insoluble polymers pDx1 and pDx5 with improved affinity for IBU and high selectivity towards erythromycin (ERY) and ERY Kd higher than 4 × 103 L/kg, when tested against a cocktail of six drugs. Characterization of the polymers shows that both pDx1 and pDx5 have similar properties, fast sorption kinetics, and ERY Kd of 13.3 × 103 for pDx1 and 6.4 × 103 for pDx5, representing 26.6 and 12.0 times the 500 L/kg threshold. The fact that new affinities and improvements in Kd can be achieved by cross-linking Dx in the presence of other molecules that promote pre-organization expands the applications of DVS cross-linked polysaccharides as sustainable, scalable, and environmentally friendly sorbents with a potential application in wastewater treatment plants (WTPs).

RESUMEN

Water use has been increasing globally by 1% per year, and recycling and re-use are critical issues compromised by the presence of pollutants. In this context, the design of novel materials and/or procedures for the large scale-removal of pollutants must be economically and environmentally feasible in order to be considered as part of the solution by emerging economies. We demonstrate that the cross-linking of biodegradable polysaccharides such as starch, dextrin, or dextrin and ß-cyclodextrin with divinyl sulfone is an innovative strategy for synthesizing insoluble and eco-friendly sorbent polymers, including pSt, pDx and pCD-Dx. The evaluation of these polymers' ability to remove ciprofloxacin (CIP), a prime example of antibiotic pollution, revealed that pSt, with a Kd of 1469 L/kg and a removal rate higher than 92%, is a favorable material. Its sorption is pH-dependent and enhanced at a mildly alkaline pH, allowing for the desorption (i.e., cleaning) and reuse of pSt through an environmentally friendly treatment with 20 mM AcONa pH 4.6. The facts that pSt (i) shows a high affinity for CIP even at high NaCl concentrations, (ii) can be obtained from affordable starting materials, and (iii) is synthesized and regenerated through organic, solvent-free procedures make pSt a novel sustainable material for inland water and seawater remediation, especially in less developed countries, due to its simplicity and low cost.

RESUMEN

Poly(caffeic acid) was synthesized and utilized for the extraction and determination of rare earth elements (REEs), thorium, and uranium. Oxidative polymerization of caffeic acid, a low-cost plant-based material, in the presence of ethylenediamine produced a granular, air-stable, and cross-linked polymer. The polymer is highly oxygenated and together with the amino group from ethylenediamine efficiently coordinates and preconcentrates these critical elements from aqueous media. Extraction was dependent on solution pH, amount of sorbent, and extraction time, while the concentration and flow rate of the desorption solution governed the recovery efficiency. Removal and recovery efficiencies greater than 98 and 90%, respectively, and low levels of detection ranging from 0.1 to 2.9 ng/L were achieved. Determination of these strategic elements in the presence of potentially interfering ions as well as in complex matrices such as well water and produced water samples also was demonstrated. The capacity of poly(caffeic acid) was determined with lanthanum as a representative REE to be 161.7 mg/g, establishing the promise of poly(caffeic acid) for larger-scale extractions in addition to the ability to screen sources for the presence of REEs.

RESUMEN

Sample pretreatment is essential for trace analysis of pesticides in complex food and environment matrices. Recently, organic-inorganic hybrid materials have gained increasing attention in pesticide extraction and preconcentration. This review highlighted the common organic-inorganic hybrid materials used as absorbents in sample pretreatment for pesticide detection. Furthermore, the preparation and characterization of organic-inorganic hybrid materials were summarized. To obtain a deep understanding of adsorption toward target analytes, the adsorption mechanism and absorption evaluation were discussed. Finally, the applications of organic-inorganic hybrid materials in sample pretreatment techniques and perspectives in the future are also discussed.

Asunto(s)

Plaguicidas , Plaguicidas/análisis , Extracción en Fase Sólida/métodos , Adsorción

RESUMEN

The present study concerns the sorption of 137Cs and 152+154Eu from low-level radioactive waste (LLW) by bentonite phosphate modified with nickel (BPN) sorbent material. BPN was synthesized using the precipitation method and characterized using various analytical techniques such as Fourier transform infrared (FT-IR), scanning electron microscope (SEM), X-ray fluorescence (XRF), and X-ray diffraction (XRD). The sorption data show that 90 min is enough time to reach equilibrium. The distribution coefficients of 137Cs and 152+154Eu were studied as a function of pH. The distribution coefficient Kd was 2122.2 mL g-1 and 1076.5 mL g-1 for 137Cs and 152+154Eu at pH 9 and 4. The adsorption capacity of BPN has values of 31.1 and 28.2 mg g-1 for 137Cs and 152+154Eu, respectively. The effect of interfering species shows that the rate of adsorption of 137Cs and 152+154Eu slightly decreases as the concentration of the interfering species increases. The investigation of BPN for removing 137Cs and 152+154Eu radionuclides was conducted using a real LLW sample. Results showed that the BPN is appropriate to remove 137Cs and 152+154Eu from liquid radioactive waste and can be considered a potential composite for the purification of effluent polluted with these radionuclides.

Asunto(s)

Residuos Radiactivos , Contaminantes Químicos del Agua , Bentonita/química , Níquel , Fosfatos , Espectroscopía Infrarroja por Transformada de Fourier , Adsorción , Radioisótopos de Cesio , Concentración de Iones de Hidrógeno , Cinética , Contaminantes Químicos del Agua/análisis

RESUMEN

Core-shell SiO2@CIM-80(Al) microspheres were synthesized, characterized, and used as novel sorbent in a dispersive miniaturized solid-phase extraction (D-µSPE) method for the determination of fourteen polycyclic aromatic hydrocarbons (PAHs) in wastewaters by ultra-high performance liquid chromatography coupled to a fluorescence detector (UHPLC-FD). A Doehlert experimental design permitted to optimize the main parameters affecting the microextraction procedure, intending the obtaining of a simple approach. Optimized extraction conditions include 13 mg of SiO2@CIM-80(Al) microparticles (~2 mg CIM-80(Al)), 2.5 min of extraction time, 0.125 mL of acetonitrile (ACN) as desorption solvent and 0.5 min of desorption time. The entire method showed adequate analytical performance with limits of detection down to 5 ng L-1, and inter-day precision lower than 14.1% for a concentration level of 0.5 µg L-1. The extraction capability of SiO2@CIM-80(Al) microspheres was compared to that obtained with commercially available silica microspheres and the neat MOF CIM-80(Al), demonstrating the advantages of the use of MOF core-shell sorbents in D-µSPE.

RESUMEN

A mixture of SO2 and air was continuously injected in a fixed bed reactor containing a CuO/SBA-15 sorbent material and submitted to an isothermal temperature between 325 and 400 °C. The SO2 emissions were measured at the exit of the reactor. Different isothermal temperatures, different injected SO2 concentrations and different sorbent masses, all representative of industrial conditions, were tested. The purpose of the paper was to propose efficient global models which simulate the breakthrough curves whatever the experimental conditions. A simplified model was first considered assuming that the oxidation and trapping processes can occur on each copper site. The values of the four kinetic parameters which are involved were determined solving this model using Scilab software and an optimization routine. Because this model failed to reproduce in a satisfying way the breakthrough curves for different sorbent masses, a second model was introduced which involves surface and bulk trapping sites and six kinetic parameters. The breakthrough curves simulated with this second model following the same resolution techniques were in better agreement with the experimental ones, whatever the experimental conditions. For comparison, a simulation of the breakthrough curves returned by a model with bulk diffusion was presented.

RESUMEN

Several combinations of high sulfur affinity elements of Cu, Zn, Fe, and Al were used to prepare sorbent materials that remove hydrogen sulfide (H2S) from air contaminated streams. The combination of these four elements in composite crystallinity structure resembling hydrotalcite-like and aurichalcite-like compounds showed excellent H2S uptake. Further tuning of the relative ratio among these elements resulted in outstanding H2S uptake. XRD revealed that the final sorbent material was featured by crystallinity structure that had two adjacent lower reflection angles. The experimental test showed H2S uptake was around 39% of the sorbent material weight when the concentration of H2S in the outlet was less than 0.5% of its concentration in the inlet. The sorbent material showed high sulfur removal efficiency at ambient temperature without prior calcination.

RESUMEN

Hemoperfusion is a kind of medical device which contacts directly with blood.In the application,fully considering the interaction between the blood and the sorbent material,so as to improve the blood compatibility is particularly important.With the development of medical science,chemistry and biomedical engineering,a variety of new materials of hemoperfusion have been studied and the blood compatibility of hemoperfusion sorbent has also been greatly improved,making the range of hemoperfusion clinical applications increasingly wide.This paper,combining related research results in recent years,reviews the research progress of the hemoperfusion adsorbent's blood compatibility in recent years.